Big tires on our Ninja had been a quest on many topics.But just put a wider tire on the rear 3.5" mini rim is not a total solution.Accept for the balloon look we gain very little,if any,out of that big tire.The side walls are squeesed so much that the shoulder will never be able or ever touch the road.Grip will never be obtimised.
To make most out of a wider tires we must be able to put the whole rubber on the ground.To do this we need wider rim.The biggest tire suitable for a 3.5"rim is size 140 but std it should be 130.
To put on a prefered 150 tires we need 4.5" rim.The maximun safe size on 4.5" rim is a 160 tire.
I've been thinking of this since 1st day I got my 250.Untill lately when Kawasaki Thailand released there new er6n
(in US they call it Ninja 650R) that I see the way to upgrade my rear tire.After fumbling around with planning measuring and calculating for a month I have myself a go.I ordered a brand new er6n rim,new sprocket coupling,rear break disc and one socket bolt(why one-see text).
To put on a wider rim I needed to do some basic modification.
Here's how.
Std Ninja Hub damper
Std er6n Hub damper
NJ's coupling.The bolts are wider apart then er's
er's coupling
Comparison:Top er's,below Ninja's
Remove the bearings out of hub.The bearing on er is bigger # 6204.The ID is 20 mm compare to 17 mm on Ninja.As well as the collar.The ID is 20mm.These holes must be made smaller by inserting a bushing reduceing the ID to 17mm so that the Ninja's original axle can be used.It's a 17mm diameter.Other option is to change the bearing to # 6303 which has The OD=er's but ID=NJ's.But why spend more.A small bushing cost next to nothing.
Knock out the bearings.Carefull not to damage the seals
er's bearing on NJ's axle.Look how loose it is.
Next on the list is the break caliper holder,hub sleeve and the two collars.They must be shave off a little.The er's hub is 15mm wider than NJ's.So reducing the total width by 15mm is essencial.
This holder is way to thick.Shave!
To make long story short!
These are all the parts that need modifying.
The sprocket will also go under butcher's knive.
The dismantle and measuring took me a couple of hours.Then took the parts to the milling shop before noon.Believe it or not
I got everything back same day before dark.Cost me 2000 Baht (57$).
I wrote somewhere if it takes more then 4 hrs I'll go banana.OK,must admit,this time no banana.
Assembly was done next day.
Lets go on.
Finished parts back from shop.Look carefully.Can you see the bushings?They were locked in with permanent locktite
The sprocket,raw.The original holes was filled using epoxi steel then painted
Filled and painted
Assembling was kind of streight forward.Backward of dismantling.The er original seals were used as they do fit NJ's collar.
Bearing back in
Seal on.Put some grease on it's lips.
Remember the one bolt I mentioned earlier?As the disc on er rim uses 4 instead of 3 on NJ.I reuse those 3 bolts +the one I bought.
Sprocket in place.See any trace? yeah,FI use only 43 teeth.
Check left,check right.Nice fit.
The most difficult mod on this project is the caliper holder.I shaved it off 11mm.In this form it's imposible to put it back on.On the right swing arm there's a stopper which take the rotating force of the holder.I handmade the next mod myself.It might look a little scary but when we break hard the rotating force will push the holder on to the stopper.No problem here.On the other hand if you CAN drive backward(?) fast and break hard the lower part of the holder might break.But who can do that.
Seen here is the holder and the stopper.How can this fit?No way.
I hand sew the original grove completely off and filled it smooth.
Cut holder and the stopper.Good fit.
Now put everything back on conventional way,start engine,put it in gear and rev.
Look terrible without tire but who's looking.
The tire I use is Battlax BT-39(same in the front)size 150/70-17.It fits perfect.Leaving plenty of space between tire and chain.On right side the gap to swing arm is not much only around 5 mil.So 150size is the widest for this mod.
Lots of clearance to chain guard...........
..........but not much to right swingarm.Enough though.
Finished product.A work of two days and brain storn for a month.Not a single mistake in calculation.
What would a write up be without a road test.
Ok,just a small one.
I headed out to my....em....personal race track?It's just a small junction next to my house.No traffic.
After ridding over some dust and sand for awhile(another way to get rid of the oilly stuff on the tire quick)it's time to test the handling.
I must say the bike behave differently.It wants to stand up(streighten up)more then before.I must hang out more into the curve to compensate.I have been using the same tire in smaller size(130) and tried out on this junction many times before but the gain in grip on this new bigger tire was .......Oh wow!And the good look of it wow wow.Used up the rubber all the way to the shoulder. wow wow wow!
I was in such fun that my wife who's takking the shots must ask me to stop.She's getting dizy just by watching me go round and round for half an hour.
Yeah,that's me haveing fun.I know I know.............safty gear!
If I just open up my knees it will scab the road but you know bare knee and cement it's a no go.
The tire was used up to the shoukder
Summery:I used to say somewhere before that I like do things myself.And this one is one of the many project I've done.Man,I love what I'm doing.
I cost for all of this was around 16000 Baht(431 US$).In my oppenion the money was well spent.
To make most out of a wider tires we must be able to put the whole rubber on the ground.To do this we need wider rim.The biggest tire suitable for a 3.5"rim is size 140 but std it should be 130.
To put on a prefered 150 tires we need 4.5" rim.The maximun safe size on 4.5" rim is a 160 tire.
I've been thinking of this since 1st day I got my 250.Untill lately when Kawasaki Thailand released there new er6n
(in US they call it Ninja 650R) that I see the way to upgrade my rear tire.After fumbling around with planning measuring and calculating for a month I have myself a go.I ordered a brand new er6n rim,new sprocket coupling,rear break disc and one socket bolt(why one-see text).
To put on a wider rim I needed to do some basic modification.
Here's how.
Std Ninja Hub damper
Std er6n Hub damper
NJ's coupling.The bolts are wider apart then er's
er's coupling
Comparison:Top er's,below Ninja's
Remove the bearings out of hub.The bearing on er is bigger # 6204.The ID is 20 mm compare to 17 mm on Ninja.As well as the collar.The ID is 20mm.These holes must be made smaller by inserting a bushing reduceing the ID to 17mm so that the Ninja's original axle can be used.It's a 17mm diameter.Other option is to change the bearing to # 6303 which has The OD=er's but ID=NJ's.But why spend more.A small bushing cost next to nothing.
Knock out the bearings.Carefull not to damage the seals
er's bearing on NJ's axle.Look how loose it is.
Next on the list is the break caliper holder,hub sleeve and the two collars.They must be shave off a little.The er's hub is 15mm wider than NJ's.So reducing the total width by 15mm is essencial.
This holder is way to thick.Shave!
To make long story short!
These are all the parts that need modifying.
The sprocket will also go under butcher's knive.
The dismantle and measuring took me a couple of hours.Then took the parts to the milling shop before noon.Believe it or not
I got everything back same day before dark.Cost me 2000 Baht (57$).
I wrote somewhere if it takes more then 4 hrs I'll go banana.OK,must admit,this time no banana.
Assembly was done next day.
Lets go on.
Finished parts back from shop.Look carefully.Can you see the bushings?They were locked in with permanent locktite
The sprocket,raw.The original holes was filled using epoxi steel then painted
Filled and painted
Assembling was kind of streight forward.Backward of dismantling.The er original seals were used as they do fit NJ's collar.
Bearing back in
Seal on.Put some grease on it's lips.
Remember the one bolt I mentioned earlier?As the disc on er rim uses 4 instead of 3 on NJ.I reuse those 3 bolts +the one I bought.
Sprocket in place.See any trace? yeah,FI use only 43 teeth.
Check left,check right.Nice fit.
The most difficult mod on this project is the caliper holder.I shaved it off 11mm.In this form it's imposible to put it back on.On the right swing arm there's a stopper which take the rotating force of the holder.I handmade the next mod myself.It might look a little scary but when we break hard the rotating force will push the holder on to the stopper.No problem here.On the other hand if you CAN drive backward(?) fast and break hard the lower part of the holder might break.But who can do that.
Seen here is the holder and the stopper.How can this fit?No way.
I hand sew the original grove completely off and filled it smooth.
Cut holder and the stopper.Good fit.
Now put everything back on conventional way,start engine,put it in gear and rev.
Look terrible without tire but who's looking.
The tire I use is Battlax BT-39(same in the front)size 150/70-17.It fits perfect.Leaving plenty of space between tire and chain.On right side the gap to swing arm is not much only around 5 mil.So 150size is the widest for this mod.
Lots of clearance to chain guard...........
..........but not much to right swingarm.Enough though.
Finished product.A work of two days and brain storn for a month.Not a single mistake in calculation.
What would a write up be without a road test.
Ok,just a small one.
I headed out to my....em....personal race track?It's just a small junction next to my house.No traffic.
After ridding over some dust and sand for awhile(another way to get rid of the oilly stuff on the tire quick)it's time to test the handling.
I must say the bike behave differently.It wants to stand up(streighten up)more then before.I must hang out more into the curve to compensate.I have been using the same tire in smaller size(130) and tried out on this junction many times before but the gain in grip on this new bigger tire was .......Oh wow!And the good look of it wow wow.Used up the rubber all the way to the shoulder. wow wow wow!
I was in such fun that my wife who's takking the shots must ask me to stop.She's getting dizy just by watching me go round and round for half an hour.
Yeah,that's me haveing fun.I know I know.............safty gear!
If I just open up my knees it will scab the road but you know bare knee and cement it's a no go.
The tire was used up to the shoukder
Summery:I used to say somewhere before that I like do things myself.And this one is one of the many project I've done.Man,I love what I'm doing.
I cost for all of this was around 16000 Baht(431 US$).In my oppenion the money was well spent.
